Change From Baseline in Attention Deficit Hyperactivity Disorder Rating Scale-fourth Edition (ADHD-RS-IV) Total Score at Week 10/13 - Last Observation Carried Forward (LOCF) [ Time Frame: Baseline and Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The ADHD-RS-IV consists of 18 items scored on a 4-point scale ranging from 0 (no symptoms) to 3 (severe symptoms) with total score ranging from 0 to 54. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Secondary Outcome Measures:

Percentage of Participants With Improvement on Clinical Global Impression-Improvement (CGI-I) Scores [ Time Frame: Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

Clinical Global Impression-Improvement (CGI-I) consists of a 7-point scale ranging from 1 (very much improved) to 7 (very much worse). Improvement is defined as a score of 1 (very much improved) or 2 (much improved) on the scale. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in the Weiss Functional Impairment Rating Scale - Parent Report (WFIRS-P) Learning and School Domain Scores at Week 10/13 - LOCF [ Time Frame: Baseline and Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The WFIRS-P Learning in School Domain is the mean of 10 items, ranging from 0 (never/not at all) to 3 (very often/very much). Higher scores indicate greater functional impairment. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in the WFIRS-P Family Domain Score at Week 10/13 - LOCF [ Time Frame: Baseline and Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The WFIRS-P Family Domain is the mean of 10 items, ranging from 0 (never/not at all) to 3 (very often/very much). Higher scores indicate greater functional impairment. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Clinical Global Impression-Severity of Illness (CGI-S) - LOCF [ Time Frame: Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

CGI-S assesses the severity of the subject's condition on a 7-point scale ranging from 1 (normal, not at all ill) to 7 (among the most extremely ill). Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Health Utilities Index-2/3 (HUI 2/3) Scores - LOCF [ Time Frame: Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

HUI is used to describe health status and to obtain utility scores by collecting data using one or more questionnaires in formats selected to match the specific study design criteria. Scoring ranges from 0.00 (dead) to 1.00 (perfect health). Higher scores represent better health status. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in the WFIRS-P Global Score at Week 10/13 - LOCF [ Time Frame: Baseline and Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The WFIRS-P Global Score is the mean of 50 items, ranging from 0 (never/not at all) to 3 (very often/very much). Higher scores indicate greater functional impairment. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in the WFIRS-P Academic Performance Domain Score at Week 10/13 - LOCF [ Time Frame: Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The WFIRS-P Academic Performance Domain is the mean of 4 items, ranging from 0 (never/not at all) to 3 (very often/very much). Higher scores indicate greater functional impairment. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in the WFIRS-P Behavior in School Domain Score at Week 10/13 - LOCF [ Time Frame: Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The WFIRS-P Behavior in School Domain is the mean of 6 items, ranging from 0 (never/not at all) to 3 (very often/very much). Higher scores indicate greater functional impairment. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in the WFIRS-P Life Skills Domain Score at Week 10/13 - LOCF [ Time Frame: Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The WFIRS-P Life Skills Domain is the mean of 10 items, ranging from 0 (never/not at all) to 3 (very often/very much). Higher scores indicate greater functional impairment. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in the WFIRS-P Child Self-Concept Domain Score at Week 10/13 - LOCF [ Time Frame: Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The WFIRS-P Child Self-Concept Domain is the mean of 3 items, ranging from 0 (never/not at all) to 3 (very often/very much). Higher scores indicate greater functional impairment. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in the WFIRS-P Social Domain Score at Week 10/13 - LOCF [ Time Frame: Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The WFIRS-P Social Domain is the mean of 7 items, ranging from 0 (never/not at all) to 3 (very often/very much). Higher scores indicate greater functional impairment. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in the WFIRS-P Risk Domain Score at Week 10/13 - LOCF [ Time Frame: Up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: No ]

The WFIRS-P Risk Domain is the mean of 10 items, ranging from 0 (never/not at all) to 3 (very often/very much). Higher scores indicate greater functional impairment. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Change From Baseline in Brief Psychiatric Rating Scale for Children (BPRS-C) Total Score at Weeks 10/13 - LOCF [ Time Frame: Baseline and up to 10 weeks for children aged 6-12 years and up to 13 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: Yes ]

The BPRS-C characterizes childhood behavioral and emotional symptomatology. A total of 21 items are rated on a scale from 0 (not present) to 6 (extremely severe) with a total score ranging from 0 to 126. A decrease in score indicates a reduction in psychopathology. Outcome measure is at 10 weeks for ages 6-12 years and at 13 weeks for ages 13-17 years.

Structure Side-Effect Questionnaire [ Time Frame: Up to 12 weeks for children aged 6-12 years and up to 15 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: Yes ]

The Structured Side-effect Questionnaire is a simple checklist of 17 side effects. The subject indicates whether a side effect has occurred since the last visit by marking 'yes' on the checklist for each of the events listed. Outcome measure is at 12 weeks for ages 6-12 years and at 15 weeks for ages 13-17 years.

Columbia-Suicide Severity Rating Scale (C-SSRS) [ Time Frame: Up to 12 weeks for children aged 6-12 years and up to 15 weeks for adolescents aged 13-17 years ] [ Designated as safety issue: Yes ]

C-SSRS is a semi-structured interview that captures the occurence, severity, and frequency of suicide-related thoughts and behaviors during the assessment period. The interview includes definitions and suggested questions to solicit the type of information needed to determine if a suicide-related thought or behaviour occurred. The assessment is done by the nature of the responses, not by a numbered scale. Outcome measure is at 12 weeks for ages 6-12 years and at 15 weeks for ages 13-17 years.

Male or female, aged 6 17 years at the time of consent/assent at Screening (Visit 1).

Subject's parent or legally authorised representative (LAR) must provide signature of informed consent, and there must be documentation of assent (if applicable) by the subject indicating that the subject is aware of the investigational nature of the study and the required procedures and restrictions in accordance with the International Conference on Harmonisation (ICH) Good Clinical Practice (GCP) Guidance E6, and applicable regulations before completing any study related procedures at Screening (Visit 1).

Subject meets Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR) criteria for a primary diagnosis of ADHD, combined sub-type, hyperactive/impulsive sub-type, or inattentive sub-type based on a detailed psychiatric evaluation using the Kiddie Schedule for Affective Disorders and Schizophrenia - Present and Lifetime version (K-SADS-PL).

Subject has a minimum ADHD-RS-IV total score of 32 at Baseline (Visit 2).

Subject has a minimum CGI-S score of 4 at Baseline (Visit 2).

Subject is functioning at an age-appropriate level intellectually, as judged by the Investigator.

Subject and parent/LAR understand, are willing, able, and likely to fully comply with the study procedures and restrictions defined in this protocol.

Subject is able to swallow intact tablets and capsules.

Subject who is a female of child-bearing potential (FOCP), defined as greater than or equal to 9 years of age or <9 years of age and is menarchal, must have a negative serum beta Human Chorionic Gonadotropin (hCG) pregnancy test at Screening (Visit 1) and a negative urine pregnancy test at Baseline (Visit 2) and agree to comply with any applicable contraceptive requirements of the protocol.

Subject has supine and standing blood pressure (BP) measurement within the 95th percentile for age, sex, and height

Subject is well-controlled on their current medication, with acceptable tolerability, and the parent/caregiver does not object to the current medication.

Subject has any condition or illness including a clinically significant abnormal Screening (Visit 1) laboratory values which, in the opinion of the Investigator, represents an inappropriate risk to the subject and/or could confound the interpretation of the study. Mild stable asthma treated without the use of beta-2 agonist is not exclusionary.

Subject has a known family history of sudden cardiac death, ventricular arrhythmia, or QT prolongation.

Subjects with orthostatic hypotension or a known history of hypertension.

Subject has glaucoma.

Subject has clinically significant ECG findings as judged by the Investigator with consideration of the central ECG laboratory's interpretation.

Subject has a history of a seizure disorder (other than a single childhood febrile seizure occurring before the age of 3 years) or the presence of a serious tic disorder including Tourette's Syndrome.

Current use of any prohibited medication or other medications, including monoamine oxidase inhibitors, herbal supplements, that affect BP or heart rate potent CYP2D6 inhibitors, medications known to prolong the QT/QTc interval, medications that lower seizure threshold, pressor agents, beta-2 agonists, medications that affect noradrenaline, medications that have central nervous system (CNS) effects or affect cognitive performance, such as sedating antihistamines and decongestant sympathomimetics (inhaled bronchodilators are permitted) or a history of chronic use of sedating medications [ie, antihistamines]) in violation of the protocol specified washout criteria at Baseline (Visit 2).

Subject has a history of alcohol or other substance abuse or dependence, as defined by DSM-IV (with the exception of nicotine) within the last 6 months.

Subject has taken another investigational product within 30 days prior to Baseline (Visit 2).

Subject is significantly overweight based on Center for Disease Control and Prevention Body Mass Index (BMI)-for-age gender specific charts at the Screening (Visit 1). Significantly overweight is defined as a BMI >95th percentile.

Children aged 6 12 years with a body weight of less than 25kg or adolescents aged 13 17 years with a body weight of less than 34kg or greater than 91kg at Screening (Visit 1).

Subject has a known or suspected allergy, hypersensitivity, or clinically significant intolerance to guanfacine hydrochloride or atomoxetine hydrochloride, or any components found in SPD503 or STRATTERA.

Clinically important abnormality on drug and alcohol screen (excluding the subject's current ADHD stimulant if applicable) at Screening (Visit 1)

Subject is female and is pregnant or currently lactating.

Subject failed screening or was previously enrolled in this study.

Subject is currently considered a suicide risk in the opinion of the Investigator, has previously made a suicide attempt, or has a prior history of, or is currently demonstrating active suicide ideation. Subjects with intermittent passive suicidal ideation are not necessarily excluded based on the assessment of the Investigator.

History of failure to respond to an adequate trial of an α2-agonist or atomoxetine hydrochloride for the treatment of ADHD (consisting of an appropriate dose and adequate duration of therapy in the opinion of the investigator).

Subjects with renal or hepatic insufficiency.

Contacts and Locations

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01244490